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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Aspectos clínicos, epidemiológicos e etiológicos de 82 casos de rinossinusite fúngica no Rio Grande do Sul / Clinical, epidemiological and etiological aspects of 82 cases of fungal rhinosinusitis in Rio Grande do Sul

Cardoso, Isabel Cristina Espíndola January 2016 (has links)
Descrição: A rinossinusite fúngica (RSF) é uma infecção oportunística, caracterizada pela inflamação da mucosa nasal e dos seios paranasais. É considerada um problema emergente na clínica médica diária, com prevalência aumentada nas últimas décadas, com etiologia nos mais diversos fungos ubíquos. Objetivos: Este trabalho objetivou analisar todos os casos de RSF pertencentes ao banco de dados do Laboratório de Micologia da Irmandade da Santa Casa de Misericórdia de Porto Alegre, no período de 28 anos (1986-2014), relacionando-os com as características clínicas e epidemiológicas. Materiais e métodos: O estudo foi retrospectivo observacional, resultando em uma série de 82 casos, confirmados histopatologicamente e pelos exames micológicos para identificação de fungos, comparados-os com os achados nas imagens radiológicas. Resultados: Foram identificados 54 casos de RSF por aspergilose, com predominância do agente etiológico Aspergillus fumigatus (14/54), e 27 casos de RSF por fungos diferentes do gênero Aspergillus, com superioridade de isolamento de agentes responsáveis por hialohifomicoses (12/27). Configurado, nestes achados, o ineditismo de três casos em nosso meio, com destaque para o primeiro caso de RSF e infecção humana por Trichoderma asperellum. Conclusões: Estes achados representam a maior casuística brasileira identificada, podendo contribuir para uma melhor compreensão epidemiológica, melhorando os critérios de suspeição médica, refletindo na efetividade dos tratamentos, principalmente, no diagnóstico dos casos de RSF invasiva, com altas taxas de mortalidade. / Description: The fungal rhinosinusitis (FRS) is an opportunistic infection characterized by inflammation of the nasal mucosa and sinuses. It is considered an emerging problem in daily medical practice, with prevalence increased in recent decades, with etiology in diverse ubiquitous fungi. Objectives: This study aimed to analyze all cases of RSF belonging to the Mycology Laboratory of the database of the Brotherhood of the Santa Casa of Misericordia Porto Alegre during the period of 28 years (1986-2014), relating them with the clinical and epidemiological characteristics. Methods: The study was observational retrospective, resulting in a series of 82 cases confirmed by histopathological and mycological examinations for identification of fungi, compared them with the findings on radiographs. Results: We identified 54 cases of aspergillosis by RSF, especially the etiologic agent Aspergillus fumigatus (14/54), and 27 cases of RSF different fungi Aspergillus, with insulation superiority of agents responsible for hyalohyphomycosis (12/27). Configured, these findings, the three cases unprecedented in our country, especially the first case of human infection with RSF and Trichoderma asperellum. Conclusions: These findings represent the largest identified Brazilian series and can contribute to a better epidemiological understanding, improving clinical suspicion criteria, reflecting the effectiveness of treatments, mainly in diagnosing cases of invasive RSF, with high mortality rates.
12

Aspectos clínicos, epidemiológicos e etiológicos de 82 casos de rinossinusite fúngica no Rio Grande do Sul / Clinical, epidemiological and etiological aspects of 82 cases of fungal rhinosinusitis in Rio Grande do Sul

Cardoso, Isabel Cristina Espíndola January 2016 (has links)
Descrição: A rinossinusite fúngica (RSF) é uma infecção oportunística, caracterizada pela inflamação da mucosa nasal e dos seios paranasais. É considerada um problema emergente na clínica médica diária, com prevalência aumentada nas últimas décadas, com etiologia nos mais diversos fungos ubíquos. Objetivos: Este trabalho objetivou analisar todos os casos de RSF pertencentes ao banco de dados do Laboratório de Micologia da Irmandade da Santa Casa de Misericórdia de Porto Alegre, no período de 28 anos (1986-2014), relacionando-os com as características clínicas e epidemiológicas. Materiais e métodos: O estudo foi retrospectivo observacional, resultando em uma série de 82 casos, confirmados histopatologicamente e pelos exames micológicos para identificação de fungos, comparados-os com os achados nas imagens radiológicas. Resultados: Foram identificados 54 casos de RSF por aspergilose, com predominância do agente etiológico Aspergillus fumigatus (14/54), e 27 casos de RSF por fungos diferentes do gênero Aspergillus, com superioridade de isolamento de agentes responsáveis por hialohifomicoses (12/27). Configurado, nestes achados, o ineditismo de três casos em nosso meio, com destaque para o primeiro caso de RSF e infecção humana por Trichoderma asperellum. Conclusões: Estes achados representam a maior casuística brasileira identificada, podendo contribuir para uma melhor compreensão epidemiológica, melhorando os critérios de suspeição médica, refletindo na efetividade dos tratamentos, principalmente, no diagnóstico dos casos de RSF invasiva, com altas taxas de mortalidade. / Description: The fungal rhinosinusitis (FRS) is an opportunistic infection characterized by inflammation of the nasal mucosa and sinuses. It is considered an emerging problem in daily medical practice, with prevalence increased in recent decades, with etiology in diverse ubiquitous fungi. Objectives: This study aimed to analyze all cases of RSF belonging to the Mycology Laboratory of the database of the Brotherhood of the Santa Casa of Misericordia Porto Alegre during the period of 28 years (1986-2014), relating them with the clinical and epidemiological characteristics. Methods: The study was observational retrospective, resulting in a series of 82 cases confirmed by histopathological and mycological examinations for identification of fungi, compared them with the findings on radiographs. Results: We identified 54 cases of aspergillosis by RSF, especially the etiologic agent Aspergillus fumigatus (14/54), and 27 cases of RSF different fungi Aspergillus, with insulation superiority of agents responsible for hyalohyphomycosis (12/27). Configured, these findings, the three cases unprecedented in our country, especially the first case of human infection with RSF and Trichoderma asperellum. Conclusions: These findings represent the largest identified Brazilian series and can contribute to a better epidemiological understanding, improving clinical suspicion criteria, reflecting the effectiveness of treatments, mainly in diagnosing cases of invasive RSF, with high mortality rates.
13

Identificação biométrica de pessoas via características dos seios paranasais obtidas de tomografias computadorizadas / Biometric human identification by means of paranasal sinuses features obtained from computed tomographys

Souza Júnior, Luis Antonio [UNESP] 05 August 2016 (has links)
Submitted by Luís Antonio de Souza Júnior null (lu.playon@gmail.com) on 2016-09-12T15:53:45Z No. of bitstreams: 1 Dissertacao_Luis_Souza_2016_final.pdf: 13262847 bytes, checksum: 14720c149fae5d6dcaceedbc097f8aed (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-09-14T19:26:15Z (GMT) No. of bitstreams: 1 souzajunior_la_me_sjrp.pdf: 13262847 bytes, checksum: 14720c149fae5d6dcaceedbc097f8aed (MD5) / Made available in DSpace on 2016-09-14T19:26:15Z (GMT). No. of bitstreams: 1 souzajunior_la_me_sjrp.pdf: 13262847 bytes, checksum: 14720c149fae5d6dcaceedbc097f8aed (MD5) Previous issue date: 2016-08-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A identificação biométrica de pessoas na área forense está em constante estudo para facilitar e melhorar as maneiras de identificação mediante a avaliação de diversas estruturas que podem ser utilizadas como características biométricas. Os seios paranasais, cavidades ósseas presentes no crânio, apresentam alta individualidade e permanência, podendo ser utilizados em sistemas biométricos forenses. As maneiras de representação digital dos seios paranasais são modalidades de exames médicos, conhecidos como raios-X e tomografia computadorizada. As imagens de raios-X como ferramentas para obtenção de características dos seios paranasais apresentam alta aplicação nos trabalhos correlatos, entretanto, nesta modalidade de imagem, algumas desvantagens, como a baixa qualidade de resolução dificultam a identificação dos seios paranasais. Com a tomografia computadorizada, uma nova avaliação pode ser realizada para a obtenção das características dos seios paranasais, visto que esta modalidade de exame gera uma sequência de imagens com qualidade superior, tornando a segmentação e extração de características dos seios paranasais mais simples, intuitiva e precisa, facilitando seu uso em sistemas de reconhecimento biométrico. O objetivo desta dissertação foi desenvolver um novo método de identificação humana utilizando estruturas dos seios paranasais, obtidas de imagens de tomografia computadorizada, como características biométricas. Este método propõe avanços significativos principalmente nas etapas de segmentação e extração de características, uma vez que a segmentação das estruturas dos seios paranasais é realizada de forma automática. As características propostas como descritores são baseadas nas regiões e nas formas das estruturas dos seios paranasais. Resultados experimentais obtidos sobre uma base de dados contendo 310 imagens de tomografia computadorizada mostraram que o método automático proposto nesta dissertação obteve taxa de segmentação medida pelo Coeficiente KAPPA igual a 88,52% na segmentação dos seios frontais e 79,30% na segmentação dos seios maxilares. Com relação à identificação de pessoas, o método proposto obteve, no melhor caso, 8,99% de taxa de erro igual (EER). Assim, nesta dissertação de mestrado concluiu-se que: os seios da face podem ser utilizados com êxito para a identificação forense de pessoas, em particular os seios frontais; que os descritores de forma para os seios frontais são mais efetivos do que os descritores de região para a identificação de pessoas, enquanto que para os seios maxilares, os descritores de forma não apresentam alto valor de discriminação entre os indivíduos e; que é possível automatizar o processo de segmentação dos seios frontais e maxilares utilizando-se imagens de tomografia computadorizada. / Biometric identification of people in the forensic field is constantly being studied to facilitate and improve the identification methods through the evaluation of several structures that can be used as biometric features. The paranasal sinuses, bone cavities present in the skull, have high individuality and permanence and can be used in forensic biometric systems. The X-rays and Computed Tomography are modalities of medical examinations used for the digital representation of the paranasal sinuses. X-rays images as a tool to obtain characteristics of the paranasal sinuses are highly applicable in the related works, however, in this imaging modality, some disadvantages, such as low quality resolution, make these structures harder to acquire. With computed tomography representation, a new evaluation can be performed to obtain the paranasal sinuses features, knowing that this exam modality generates an image sequence with higher quality, making the paranasal sinuses segmentation and feature extraction simpler, intuitive and precise, facilitating its use in biometric recognition systems. The objective of this master’s dissertation was the development of a new human identification method that uses paranasal sinuses structures as biometric features, obtained from computed tomography images. This method proposes significant advances, specially on the segmentation and features extraction stages, once the segmentation of the paranasal sinuses structures is performed automatically. The characteristics proposed for the feature descriptors are based on the region and shape of the paranasal structures. The experimental results obtained from a database composed by 310 computed tomography images presented that the automatic method proposed in this dissertation showed 88.52% of frontal sinuses segmentation and 79.30% of correct maxillary sinuses segmentation using the KAPPA coefficient. Relative to the persons identification, the proposed method presented in the best case 8.99% of EER. Therefore, in this master’s dissertation, it was concluded that: the face sinuses, and in particular the frontal sinuses, can be used with success for the forensic human identification; for the human identification based on the frontal sinuses the shape descriptors are more efficient than the region descriptors, while that for the human identification based on maxillary sinuses, the shape descriptors do not presented high discrimination performance and; it is possible to automate the frontal and maxillary sinuses segmentation process using computed tomography images.
14

Aspectos clínicos, epidemiológicos e etiológicos de 82 casos de rinossinusite fúngica no Rio Grande do Sul / Clinical, epidemiological and etiological aspects of 82 cases of fungal rhinosinusitis in Rio Grande do Sul

Cardoso, Isabel Cristina Espíndola January 2016 (has links)
Descrição: A rinossinusite fúngica (RSF) é uma infecção oportunística, caracterizada pela inflamação da mucosa nasal e dos seios paranasais. É considerada um problema emergente na clínica médica diária, com prevalência aumentada nas últimas décadas, com etiologia nos mais diversos fungos ubíquos. Objetivos: Este trabalho objetivou analisar todos os casos de RSF pertencentes ao banco de dados do Laboratório de Micologia da Irmandade da Santa Casa de Misericórdia de Porto Alegre, no período de 28 anos (1986-2014), relacionando-os com as características clínicas e epidemiológicas. Materiais e métodos: O estudo foi retrospectivo observacional, resultando em uma série de 82 casos, confirmados histopatologicamente e pelos exames micológicos para identificação de fungos, comparados-os com os achados nas imagens radiológicas. Resultados: Foram identificados 54 casos de RSF por aspergilose, com predominância do agente etiológico Aspergillus fumigatus (14/54), e 27 casos de RSF por fungos diferentes do gênero Aspergillus, com superioridade de isolamento de agentes responsáveis por hialohifomicoses (12/27). Configurado, nestes achados, o ineditismo de três casos em nosso meio, com destaque para o primeiro caso de RSF e infecção humana por Trichoderma asperellum. Conclusões: Estes achados representam a maior casuística brasileira identificada, podendo contribuir para uma melhor compreensão epidemiológica, melhorando os critérios de suspeição médica, refletindo na efetividade dos tratamentos, principalmente, no diagnóstico dos casos de RSF invasiva, com altas taxas de mortalidade. / Description: The fungal rhinosinusitis (FRS) is an opportunistic infection characterized by inflammation of the nasal mucosa and sinuses. It is considered an emerging problem in daily medical practice, with prevalence increased in recent decades, with etiology in diverse ubiquitous fungi. Objectives: This study aimed to analyze all cases of RSF belonging to the Mycology Laboratory of the database of the Brotherhood of the Santa Casa of Misericordia Porto Alegre during the period of 28 years (1986-2014), relating them with the clinical and epidemiological characteristics. Methods: The study was observational retrospective, resulting in a series of 82 cases confirmed by histopathological and mycological examinations for identification of fungi, compared them with the findings on radiographs. Results: We identified 54 cases of aspergillosis by RSF, especially the etiologic agent Aspergillus fumigatus (14/54), and 27 cases of RSF different fungi Aspergillus, with insulation superiority of agents responsible for hyalohyphomycosis (12/27). Configured, these findings, the three cases unprecedented in our country, especially the first case of human infection with RSF and Trichoderma asperellum. Conclusions: These findings represent the largest identified Brazilian series and can contribute to a better epidemiological understanding, improving clinical suspicion criteria, reflecting the effectiveness of treatments, mainly in diagnosing cases of invasive RSF, with high mortality rates.
15

Achados tomográficos incidentais de opacificação sinusal em crianças e adolescentes e sua evolução clínica / Incidental tomographic findings of sinus opacification in children and adolescents and clinical follow up

Araújo Neto, Severino Aires de 04 September 2010 (has links)
Orientador: Emílio Carlos Elias Baracat / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-15T23:48:45Z (GMT). No. of bitstreams: 1 AraujoNeto_SeverinoAiresde_D.pdf: 1663996 bytes, checksum: 1b3dbcdd551ce6e32414e2763d39f942 (MD5) Previous issue date: 2010 / Resumo: Opacificações dos seios paranasais podem ser encontradas incidentalmente em tomografias de pacientes sem rinossinusite. Esses achados freqüentemente são desprovidos de significado clínico, mas podem trazer dilemas diagnósticos quando são intensos. Objetivos: verificar se anormalidades tomográficas incidentais dos SPN em crianças e adolescentes sem rinossinusite implicam em maior risco de desenvolvimento posterior de sintomas do trato respiratório superior. Casuística e Método: foi realizado um estudo de coorte com pacientes entre zero e 18 anos, submetidos à tomografia computadorizada do crânio por indicações não relacionadas à rinossinusite. As opacificações sinusais foram aferidas por um escore, a razão opacificação/desenvolvimento. A evolução clínica dos pacientes foi então avaliada por questionários durante o mês que se seguia ao exame. Resultados: dos 106 pacientes incluídos, as opacidades acometeram 56%, a maioria representada por espessamento mucoso discreto. Opacidades mais intensas, ditas suspeitas (escore = 15) impuseram maior risco de desenvolvimento de sintomas ao longo do seguimento, com odds ratio de 2,74 (IC95%: 1,10 - 6,83) em relação aos exames normais ou a opacidades discretas. Conclusão: opacidades são encontradas incidentalmente com freqüência em tomografias de crânio de crianças e adolescentes e quanto mais intensas elas são, maior é o risco de evolução posterior de quadros respiratórios / Abstract: Paranasal sinuses opacification are incidentally found on computed tomography of patients without rhinosinusitis. These findings are often of no clinical significance, however may cause diagnostic dilemmas when they are severe. Objective: to verify if incidental abnormalities of the paranasal sinuses on tomography of children and adolescents without rhinosinusitis raise the risk for development of superior respiratory tract symptoms. Methods: a cohort study was conducted on patients with ages varying from 0 to 18 years whose tomographic scans of the head were done for problems not related to rhinosinusitis. Sinuses abnormalities were measured by a score system called opacification-development ratio. Then periodical clinical follow-ups were undertaken by inquiry forms applied during the month next to the scan. Results: From a sample of 106 patients, opacities affected 56%, usually represented by mild mucousal thickening. Moderate and severe opacities, what was called suspicious (score = 15) imposed a higher risk of emerging respiratory symptoms during follow-up, at an odds ratio of 2.74 (CI95%: 1.10 - 6.83), compared with mild opacities or normal scans. Conclusion: Incidental opacities are frequently found on computed tomography of children and adolescents and the more severe they are, the higher the risk of progression to respiratory clinical manifestations afterwards / Doutorado / Saude da Criança e do Adolescente / Doutor em Saude da Criança e do Adolescente
16

Development and diagnostics of bacterial acute rhinosinusitis in young adults

Autio, T. (Timo) 10 January 2017 (has links)
Abstract Acute rhinosinusitis (ARS) is a common condition often treated with antibiotics, even though the cause is usually viral. Despite the commonness of ARS, there is limited evidence on the development and diagnosis of bacterial cases. So far, we lack prospective studies where the bacterial cause would have been confirmed with a bacterial culture of the paranasal sinus aspirate. The purpose of the study was to investigate the course of ARS with a prospective inception cohort study among young adults with ARS, using sequential and standardized methods. To differentiate viral and bacterial ARS, maxillary sinus aspiration and a bacterial culture were used as a reference standard for bacterial ARS. Fifty conscripts with ARS were recruited between February and April 2012. Eight patients (16%) had a positive culture from the maxillary sinus aspirate at 9–10 days and thus, had bacterial ARS. Viral and bacterial coinfection resulted in extensive paranasal mucosal abnormalities and increased symptoms during the episode. The paranasal mucosal abnormalities developed rapidly and remained relatively constant during the episode in both bacterial and non-bacterial ARS. A change in inflammatory biomarker levels indicated both local and systemic inflammatory responses, which were strongest at the onset of symptoms. Symptoms or their changes were of little use in diagnosing bacterial ARS, but secretion seen in the nasal cavity, posterior pharynx or middle meatus predicted bacterial ARS quite well. These results suggest that bacterial infection may modify symptoms and paranasal abnormalities already at the beginning of an ARS episode, although the spread of paranasal abnormalities may not be an etiological factor in the development of bacterial ARS. ARS involves local and systemic inflammatory responses, which are strongest at the beginning of the episode. Examination of the nose and throat is recommended for diagnosing bacterial ARS. / Tiivistelmä Nenän äkillinen sivuontelotulehdus on tavallinen tauti, jonka hoitoon käytetään paljon antibiootteja, vaikka sen aiheuttaja on useimmiten virus. Bakteerin aiheuttaman tautimuodon kehittymisestä ja diagnostiikasta ei ole julkaistu tutkimuksia, joissa potilaita olisi seurattu taudin alusta lähtien ja bakteerin olemassaolo olisi varmistettu nenän sivuontelosta otetulla bakteerinäytteellä. Tämän väitöskirjatyön tarkoituksena oli selvittää nenän äkillisen sivuontelotulehduksen kulkua käyttämällä toistuvia, standardisoituja menetelmiä. Bakteerin aiheuttama tauti todettiin poskiontelopistolla ja bakteeriviljelyllä. Tutkimukseen osallistui viisikymmentä (50) äkilliseen ylähengitystieinfektioon sairastunutta varusmiestä keväällä 2012. Kahdeksalla (16 %) potilaalla todettiin bakteerin aiheuttama tauti poskiontelopiston avulla 9–10 päivää oireiden alkamisen jälkeen. Viruksen ja bakteerin sekainfektio aiheutti laajemmat sivuonteloiden tulehduslöydökset ja voimakkaammat oireet kuin pelkän viruksen aiheuttama tauti. Sivuonteloiden tulehduslöydökset kehittyivät nopeasti ja pysyivät sekä bakteerin että viruksen aiheuttamassa taudissa varsin muuttumattomina. Tulehdusmerkkiaineiden muutokset osoittivat sekä paikallisen, että yleisen tulehdusreaktion, jotka olivat voimakkaimmillaan taudin alussa. Oireet tai niissä taudin aikana tapahtuneet muutokset eivät osoittautuneet hyviksi merkeiksi bakteerin aiheuttaman taudin toteamiseksi, mutta eritteen näkyminen nenässä, nielussa tai keskikäytävässä ennakoi hyvin bakteerin aiheuttaman sivuontelotulehduksen toteamista. Bakteeri saattaa vaikuttaa oireisiin ja sivuonteloiden tulehduslöydöksiin jo nenän äkillisen sivuontelotulehduksen alussa, mutta tulehduslöydösten laajuus ei välttämättä liity bakteerin aiheuttaman taudin kehittymiseen. Nenän äkilliseen sivuontelotulehdukseen liittyy paikallinen ja yleinen tulehdusreaktio, jotka ovat voimakkaimmillaan taudin alussa. Potilaan nenän ja nielun tutkiminen on tärkeää bakteerin aiheuttaman nenän sivuontelotulehduksen toteamiseksi.
17

Contributions à l'étude des cavités nasosinusiennes de l'adulte par la morphométrie géométrique et la simulation numérique des écoulements / A morphometric geometric and a CFD study of the sinonasal cavities

Michel, Justin 10 December 2015 (has links)
Objectif - Réaliser une étude en morphométrie géométrique pour définir la variabilité des sinus frontaux et maxillaires au sein d’une population adulte et pour l’établissement du profil biologique des individus à partir de la géométrie des sinus frontaux et maxillaires.- Valider un modèle de simulation numérique des écoulements pour l’étude de la ventilation nasosinusienne chez l’adulte et observer l’influence de la conformation sinusienne sur la ventilation nasosinusienne.Nous avons défini 20 landmarks fiables et reproductibles pour les sinus frontaux et maxillaires. Nous avons décrit la variabilité des sinus frontaux et maxillaires au sein d’un échantillon de population adulte. Enfin, nous avons mis en évidence l’existence d’allométries pour les sinus frontaux et maxillaires mais aussi l’existence d’un dimorphisme sexuel pour la conformation des sinus maxillairesNous proposons un modèle fiable de simulation numérique des écoulements à partir d’examen tomodensitométriques. Sur la base de ce modèle, nous n’avons pas mis en évidence d’influence de la conformation sinusienne sur la ventilation nasale et le conditionnement thermique de l’air inspiré et expiré. / Objectives - to conduct a morphometric geometric study in order to define the variability of the frontal and maxillary sinuses in an adult population and to determinate the sex of individuals - to validate a Computational fluid dynamic model of the nasal airflow and to describe the influence of the sinus conformation on the nasal airflow.We defined twenty reliable and reproducible landmarks for frontal and maxillary sinuses. We described the variability of the frontal and maxillary sinuses in an adult population sample. Finally, we highlighted the existence of allometries for frontal and maxillary sinuses but also the existence of a sexual dimorphism in the conformation of the maxillary sinusesComputational fluid dynamics:We offer a reliable model for numerical simulation of flows from CT examination. Based on this model, we have not shown any influence of the conformation on the nasal sinus ventilation and thermal conditioning of the inhaled and exhaled air. We showed no ventilation in the sinuses in the nasal respiratory cycle. Future studies will endeavor to define a humidity conditioning air model and a simulation model of production of NO and gas exchange between sinuses and nasal cavities.
18

Estimativa da dose e risco em pacientes Pediátricos devido a exames radiográficos dos Seios da face

PINTO, Beatriz Villa-­‐Chan Cantalupo 31 May 2015 (has links)
Submitted by Haroudo Xavier Filho (haroudo.xavierfo@ufpe.br) on 2016-04-20T17:12:27Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DISSERTAÇÃO FINAL PARA IMPRESSÃO CAPA DURA.compressed.pdf: 5438350 bytes, checksum: 6a32a2d9accc05fb896d407a8a699c4b (MD5) / Made available in DSpace on 2016-04-20T17:12:27Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DISSERTAÇÃO FINAL PARA IMPRESSÃO CAPA DURA.compressed.pdf: 5438350 bytes, checksum: 6a32a2d9accc05fb896d407a8a699c4b (MD5) Previous issue date: 2015-05-31 / CAPES / FACEPE / No presente trabalho, foi realizado um levantamento das doses recebidas por pacientes pediátricos, em exames radiográficos convencionais dos seios da face, realizados no Recife, PE. Para a realização do estudo, foram selecionados dois hospitais que atendem ao Sistema Único de Saúde, com alta demanda de exames pediátricos. Os dados dos pacientes e os parâmetros de irradiação utilizados em 159 exames radiográficos dos seios da face de crianças, com idades entre 0 e 15 anos, foram coletados, sendo 103 radiografias realizadas na projeção lateral (radiografia cavum) e 56 radiografias realizadas nas projeções pósteroanteriores em fronto-naso (FN) e mento-naso (MN) (radiografias Caldwell e Waters, respectivamente). Inicialmente, foram efetuadas as avaliações de desempenho dos dois equipamentos de raios X pertencentes aos hospitais. A partir dos valores dos rendimentos dos tubos de raios X e dos parâmetros de irradiação empregados nos exames, foram estimados os valores de kerma no ar na superfície de entrada (Ka,e) e produto kerma no ar-área (PK,A). Os valores de kerma no ar nas regiões dos olhos e da tireoide foram estimados utilizando dosímetros termoluminescentes (TLD-100). As doses absorvidas médias nos órgãos e a dose efetiva foram estimadas com o software PCXMC® a partir dos dados antropométricos, parâmetros de irradiação e do kerma no ar incidente (Ka,i), obtido com o rendimento. Os resultados mostraram que os valores de Ka,e variaram entre 0,065 mGy e 1,113 mGy, para radiografias cavum, entre 0,13 mGy e 7,99 mGy, para radiografias na incidência Caldwell e entre 0,13 mGy e 10,12 mGy, para radiografias na incidência Waters. Os valores do kerma no ar na região dos olhos variaram entre 0,001 mGy e 0,968 mGy, nas radiografias cavum, e 0,011 mGy e 0,427 mGy, nas incidências Caldwelll e Waters (conjuntamente). Na região da tireoide, os valores de kerma no ar variaram entre 5 μGy e 932 μGy, para as radiografias cavum, e 2 μGy e 972 μGy, para as incidências Caldwell e Waters. 90% dos valores de Ka,e estimados para os exames realizados no Hospital B encontram-se dentro do recomendado pela comunidade britânica, enquanto todos no Hospital A encontram-se acima. O fato do Hospital B apresentar valores de Ka,e dentro do aconselhado não significa que seu serviço esteja otimizado, devido a grande quantidade de filmes rejeitados, cuja imagem apresentava-se clara e inapropriada para o diagnóstico, elevando a dose final recebida pelo paciente pela repetição do exame. Os altos valores de Ka,e devem-se, principalmente, à utilização indiscriminada da grade antiespalhamento, não recomendada para pacientes desta idade. Os valores de PK,A variaram entre 5,7 mGy.cm2 e 92,3 mGy.cm2 para as radiografias cavum, entre 24,4 mGy.cm2 e 340,3 mGy.cm2 para as radiografias Caldwell e, entre 34,0 mGy.cm2 e 378,3 mGy.cm2 para as radiografias Waters. A partir dos dados pode-se concluir que há necessidade de otimização dos procedimentos radiográficos. / In this study, a survey was conducted in order to assess doses received by pediatric patients ongoing conventional radiographs of the sinuses, performed in Recife, PE. For the study, two hospitals of SUS (Sistema Único de Saúde), with high demand for pediatric examinations, were selected. Patient data and irradiation parameters were collected for 159 radiographs of the children’s sinuses with ages between 0 and 15. Among those, 103 radiographs were taken on the lateral projection (cavum radiography) and 56 radiographs were taken in posteroanterior projections in fronto-naso (FN) and mento-naso (MN) (Caldwell and Waters radiographs, respectively). Initially, the performance of the two X-ray equipment was evaluated. Air kerma values at the entrance surface (Ka,e), and air kerma area product (PK,A) were estimated using X-ray tubes output and irradiation parameters used in the examinations. Air Kerma values on the eyes and thyroid were estimated using thermoluminescent dosimeters (TLD-100). The average absorbed organ doses and effective dose were estimated at the PCXMC® software using the anthropometric data, irradiation parameters and the incident air kerma (Ka,i) obtained with the x-ray tube output. The results showed that Ka,e values varied between 0.065 and 1.113 mGy for cavum radiographs; between 0.13 and 7.99 mGy for Caldwell’s view; and between 0.13 and 10.12mGy for Waters’ view. The air kerma values in at the eye region varied from 0.001 mGy to 0.968 mGy for cavum radiographs, and from 0.011 mGy to 0.427 mGy for Caldwell and Waters’ views (together). In the thyroid region air kerma values ranged from 5 μGy to 932 μGy for cavum view and from 2 μGy to 972 μGy for Caldwell and Waters’ views. Tests performed at Hospital B have shown that 90% of the Ka,e values estimated during exams are within the recommended values by British Commonwealth, while all the Ka,e values in the Hospital A were above it. However, even though Hospital B presented Ka,e values within recommended values, this service was not optimized, due to the large amount of rejected films, whose image were inappropriate for diagnosis resulting in increased dose by the patient re-examination. The high Ka,e values are due mainly to the indiscriminate use of anti-scatter grid, not recommended for patient ages assessed in this study. PK,A values varied between 5.7 and 92.3 mGy.cm2 for cavum radiographs, between 24.4 and 340.3 mGy.cm2 for Caldwell’s view and between 34.0 and 378.3 mGy.cm2 for Waters’ view. Thus, it was concluded that there is need for optimization of radiographic procedures.
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Contribution of Paranasal Sinuses to the Acoustic Properties of the Nasal Tract

Havel, Miriam, Hofmann, Gert, Mürbe, Dirk, Sundberg, Johan 04 August 2020 (has links)
Background: The contribution of the nasal and paranasal cavities to the vocal tract resonator properties is unclear. Here we investigate these resonance phenomena of the sinonasal tract in isolation in a cadaver and compare the results with those gained in a simplified brass tube model. Methods: The resonance characteristics were measured as the response to sine sweep excitation from an earphone. In the brass model the earphone was placed at the closed end and in the cadaver in the epipharynx. The response was picked up by a microphone placed at the open end of the model and at the nostrils, respectively. A shunting cavity with varied volumes was connected to the model and the effects on the response curve were determined. In the cadaver, different conditions with blocked and unblocked middle meatus and sphenoidal ostium were tested. Additionally, infundibulotomy was performed allowing direct access to and selective occlusion of the maxillary ostium. Results: In both the brass model and the cadaver, a baseline condition with no cavities included produced response curves with clear resonance peaks separated by valleys. Marked dips occurred when shunting cavities were attached to the model. The frequencies of these dips decreased with increasing shunting volume. In the cadaver, a marked dip was observed after removing the unilateral occlusion of the middle meatus and the sphenoidal ostium. Another marked dip was detected at low frequency after removal of the occlusion of the maxillary ostium following infundibulotomy. Conclusion: Combining measurements on a simplified nasal model with measurements in a cadaveric sinonasal tract seems a promising method for shedding light on the acoustic properties of the nasal resonator.
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Volumetric measurements of paranasal sinuses and examination of sinonasal communication in healthy Shetland ponies: anatomical and morphometric characteristics using computed tomography

Köhler, Lisa, Schulz-Kornas, Ellen, Vervuert, Ingrid, Gittel, Claudia, Winter, Karsten, Berner, Dagmar, Gerlach, Kerstin 16 February 2022 (has links)
Background: Despite clinical importance and frequent occurrence of sinus disease, little is known about the size of paranasal sinuses and their communication in ponies and small horses. To examine the shape and volume of the paranasal sinuses and evaluate the sinonasal communication, three-dimensional (3D) reconstructions of computed tomography (CT) datasets of 12 healthy adult Shetland ponies were performed and analysed. Linear measurements of head length and width were taken. Using semi-automatic segmentation, 3D-models of all sinus compartments were created. Volumetric measurement of the seven sinus compartments were conducted and statistical analysis was performed. Sinus volumes were compared between the left and right sinuses and the relation to age and head size was evaluated. Results: Structure and shape of the paranasal sinus system in Shetland ponies was similar to that of large horses. All seven sinus compartments on each side of the head were identified (rostral maxillary sinus, ventral conchal sinus, caudal maxillary sinus, dorsal conchal sinus, middle conchal sinus, frontal sinus, sphenopalatine sinus). The existence of a bilateral cranial and a caudal system formed by a maxillary septum was visible in all 12 individuals. The volumetric sizes of the left and right sinuses did not differ significantly (p > 0.05). A positive correlation between the size of the paranasal sinuses and the head length was shown. A relation between sinus volumes and age could not be proved in adult ponies aged > six years. Communication between single sinus compartments was identified. Furthermore, communication with the nasal cavity over the nasomaxillary aperture (Apertura nasomaxillaris) and a common sinonasal channel (Canalis sinunasalis communis) as well as its splitting up into a rostral and a caudolateral channel could be seen. Examination of the sinonasal communication was challenging and only a descriptive evaluation was possible. Conclusions: Our findings concerning the size, shape and volumetric dimensions of Shetland pony CT images could help improve CT interpretation of abnormal clinical cases as well as aiding clinicians to develop and select appropriate instruments for medical inspection and treatments.

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